Method of distilling wood.



F. & G. M. POPE.

METHOD OF DISTILLIHG WOOD. APPLICATION FILED JUNE 1, 1910.

Pate'ntgd Feb. 3, 1914..

nets.

hard pitch having, a hi 'h point of volatilization and a high speci toheat.

In carrying out the process the bath is circulated upwardly through theretort until all the desired products are obtained. The .valves 14., 16and 18 are then changed to drain the retort and permit the withdrawal ofthe charge of heated Wood and the placing of a fresh charge in theretort, the bath meanwhile being circulated from the heater through theby-pass pipe 15 to the storage tank to maintain its temperature.

In carrying out the process the products which are extracted or heatdistilled from the WOOd. by the hot bath escape into the body of thebath and most of them in the form of vapor bubble up through the bathand escape through the opening 10 in the top of the retort and passthence to the condenser. The partial vacuum maintained in the upper partof the retort facilitates the escape of the vapors and reduces theamount that goes into solution in the hath. Those products which do notescape directly as vapors but are dissolved in thebath are almostimmediately distilled therefrom as soon as the bath comes in contactwith the steam escaping from the perforated pipes 9. The separation ofthe dissolved products from the bat-h is made more sure by placing theoutlet of thebath some distance above the level of the steam pipes,thereby insuring a very considerable depth of bath through which thesteam must pass and giving time for the equalization of the vaportensions of the steam and dissolved prod- These products which becomedissolved in the bath must remain dissolved therein the shortestpossible length of time, since they are almost immediately distilledfrom the bath by means of the steam.

What we claim is:

1. The method of distilling Wood consisting in placing the wood in aclosed vessel,

circulating through the vessel and over the wood from the bottomupwardly a bath desired products from the wood, 1ntr0ducing steam intothe portion of the bath above the level of the wood and therebydistilling ott therefrom such products as have become dissolved therein,and maintaining above the bath in the vessel. a pressure less thanatmospheric pressure.

3. The method of distilling wood consisting in placing the wood in aclosed vessel, circulating 'through the vessel and over the wood fromthe bottom upwardly a hot bath composed oi. the pitch which flows inliquid form from the bottom of the retort in the destructivedistillation of wood, thereby distilling the desired products from thewood, and introducing steam into that portion of the bath above thelevel oithe Wood, and thereby distilling on therefrom such of theproducts as have become dissolved therein.

In testimony whereof, we have hereunto set our hands.

FREDERICK POPE. GEORGE M. POPE.

Witnesses for Frederick Pope:

J as. L. WnLnoN, MARY E. OAHooN. Witnesses for George M. Pope:

W. M. Ronnnson,

IRA M. RAYBON.

